Unless otherwise indicated herein, the materials described herein are not prior art to the claims in the present application and are not admitted to be prior art by inclusion in this section.
At present, base stations in some radio communication systems typically transmit scheduling information on a Physical Downlink Control Channel (PDCCH) to User Equipment (UE) within cells serviced by the respective base stations. The PDCCH may be divided into a common search space and one or more specific search spaces. The PDCCH in the common search space may be transmitted with a relatively large transmitting power to ensure coverage of the common search space of the PDCCH for a given cell near the periphery of the cell. Due to the relatively large transmitting powers used to ensure coverage near cell peripheries, PDCCHs in the common search space of adjacent cells can interfere if the PDCCHs include overlapping time-frequency resources.
PDCCH resources may be mapped to time-frequency resource locations using a sub-block interleaving method to combat fast fading of wireless channels. However, the sub-block interleaving method does not address interference problems that can arise when PDCCHs in adjacent cells include overlapping time-frequency resources.